Gargantuan summer blockbuster movies are supposed to blow you away, and the critics have certainly been knocked for six by Transformers: Revenge of the Fallen. Our own Peter Bradshaw describes this Michael Bay stompathon as "like watching paint dry while getting hit over the head with a frying pan"; the Telegraph's Tim Robey says it's "impressive in much the same way that you might find it impressive to have your head used as one of the timpani during Beethoven's Ode to Joy", while Channel 4 Film's Richard Luck warns potential filmgoers: "if you don't have your ears covered and your mouth open, your ear drums'll burst".

Get the idea? This is not so much a movie as a rampant, directionless force of nature. Bay throws pixels, metal and flesh at the camera in much the same way as Jackson Pollock once chucked oils at a canvas. The results, while no less chaotic than those produced by the painter, are somewhat less pleasing to the eye.

Revenge of the Fallen sees Shia LaBeouf reprising his role as Sam Witwicky, the all-American teenager who discovered in the first film that his new VW was actually an extraterrestrial with the power to transform into a kick-ass robot, and that he (Sam) was somehow at the centre of a battle between good (Autobot) and evil (Decepticon) clans of mechanical warriors who variously want to destroy Earth and mankind, and save them.

The plot once again surrounds a Very Big Powerful Thing called the Allspark which revives dead robots, among other uses, and another Very Big Powerful Thing (this one is new) called the Matrix of Leadership. It also features an all-new villain, a nefarious Decepticon called the Fallen who is even meaner and nastier than the first film's Megatron. I'd love to tell you more, but to be frank I couldn't tell what on earth was going on half of the time amid the blitzkrieg of explosions and flying steel. Suffice to say there are at least 40 robots going at it hammer and tongs for at least 90% of the movie's terrifying two and a half hour running time. The rest is made up of rubbish one liners and a whole lot of closeups on various bits of Megan Fox.

"Bay's is a cinema on steroids, pursuing a body-builder's dream of eternal growth - it must bulge constantly outward, veins popping like twigs from its ever-flexed biceps," adds Robey. "[But] whatever performance-enhancing drugs Bay fed his CGI technicians, there clearly weren't many left over for the human cast. The worst offender is Megan Fox, first seen suggestively washing a motorbike as if modelling for a 1980s lad-mag shoot. She's less actress than action figure - it's amazing she doesn't melt in the desert heat."

"Revenge Of The Fallen isn't only louder than Transformers. It's longer, it's more explosive, it's more directionless, it's all the proof you'll ever need that more really isn't always more," adds Luck. "That it's slightly - only slightly - better than part one is solely due to the fact that the money's clearly up on screen. But by the time the umpteenth building is demolished by a stray Decepticon boot, you'll find yourself amazed at how little (an estimated) $200 million buys you these days."

"Bay has a great love of flashy effects, stroboscopic editing and loud crashes," adds Bradshaw. "He famously calls his cinematic technique 'fucking the frame'. That phrase might be brutal, but it's accurate. And there's no doubt about it: he really has given the frame a right old seeing-to this time. Bay has turned up at the frame's flat with some unguent massage oils, scented candles and a hundredweight of Viagra. It isn't long before the headboard of the frame's bed is crashing repeatedly against the wall, while the frame gazes up at the ceiling ... and I think the frame is faking it. Because this film really is quite staggeringly uninteresting."

Empire's Nick De Semlyen, however, miraculously conjures a three out of five star review, despite referring to its "baffling" plot and complete lack of ideas.

"What saves it, just about, are the effects," he writes, perhaps with one eye on an exclusive Empire visit to the set of Transformers III. "When these CG moto-men from another world duke it out, the images are often so screwy it's impossible to do anything but sit and stare. There are more flawlessly rendered money shots in the last 40 minutes alone than in a dozen less ambitious blockbusters."

If I tell you that the loudest cheer of the night at the London premiere last week in Leicester Square came at the mention of the toy manufacturer Hasbro's name just before the movie itself began, that might give you some idea of quite how mind-numbingly plasticky Revenge of the Fallen is. It is also preposterously boring. It feels like being pummelled into submission by something hugely powerful, but which you can't quite make out amid the flurry of blows. Worst of all, half the robots, particularly the bad guys, look exactly the same, so it's impossible to tell who's who, and what is happening. I have to admit my seat was a long way back from the big screen at a fairly extreme angle, and it might be a different experience at one of the excellent IMAX cinemas, for instance. But I found it impossible to enjoy Transformers, even as a spectacle, and certainly not as a piece of coherent storytelling.

What did you think? Are the critics all being a bit too po-faced? Was the movie just a big hunk of blockbuster fun? Could you tell what was going on? And could you please tell me?

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